Film deposition method

Abstract

A film deposition method includes steps of: adsorbing a silicon-containing gas on a surface of a substrate, by supplying the silicon-containing gas to the surface of the substrate; depositing a silicon nitride film, by supplying a nitriding gas to the surface of the substrate, while being activated by a first plasma, and nitriding the silicon-containing gas adsorbed on the surface of the substrate; and modifying the silicon nitride film deposited on the surface of the substrate, by supplying a treatment gas containing NH 3 and N 2 at a given ratio to the surface of the substrate, while being activated by a second plasma.

What is claimed is: 
     
         1 . A film deposition method comprising steps of:
 adsorbing a silicon-containing gas on a surface of a substrate, by supplying the silicon-containing gas to the surface of the substrate;   depositing a silicon nitride film, by supplying a nitriding gas to the surface of the substrate, while being activated by a first plasma, and nitriding the silicon-containing gas adsorbed on the surface of the substrate; and   modifying the silicon nitride film deposited on the surface of the substrate, by supplying a treatment gas containing NH 3  and N 2  at a given ratio to the surface of the substrate, while being activated by a second plasma.   
     
     
         2 . The film deposition method according to  claim 1 , wherein N 2  is higher than NH 3  in the given ratio. 
     
     
         3 . The film deposition method according to  claim 2 , wherein N 2  at least twice as much as NH 3  is included by the given ratio. 
     
     
         4 . The film deposition method according to  claim 3 , wherein N 2  at least three times as much as NH 3  is included by the given ratio. 
     
     
         5 . The film deposition method according to  claim 1 , wherein the nitriding gas is an NH 3 -containing gas. 
     
     
         6 . The film deposition method according to  claim 5 , wherein the nitriding gas is a gas that does not contain N 2 . 
     
     
         7 . The film deposition method according to  claim 5 , wherein the nitriding gas further contains Ar and H 2 . 
     
     
         8 . The film deposition method according to  claim 1 , wherein the treatment gas further contains Ar. 
     
     
         9 . The film deposition method according to  claim 1 , wherein a position where the second plasma is generated is closer to the surface of the substrate than a position where the first plasma is generated. 
     
     
         10 . The film deposition method according to  claim 9 , wherein the step of adsorbing the silicon-containing gas, the step of depositing the silicon nitride film, and the step of modifying the silicon nitride film are successively repeated to deposit the silicon nitride film to have a given thickness. 
     
     
         11 . The film deposition method according to  claim 10 , further comprising the steps of:
 supplying a purge gas to the surface of the substrate between the step of adsorbing the silicon-containing gas and the step of depositing the silicon nitride film; and   supplying the purge gas to the surface of the substrate between the step of modifying the silicon nitride film and the step of adsorbing the silicon-containing gas.   
     
     
         12 . The film deposition method according to  claim 11 ,
 wherein the substrate is placed on a surface of a turntable provided in a process chamber along a circumferential direction,   wherein above the turntable in the process chamber, a silicon-containing gas supply area, a first purge gas supply area, a nitriding gas supply area, a treatment gas supply area, and a second purge gas supply area are successively provided along a rotational direction of the turntable, and   wherein the step of adsorbing the silicon-containing gas, the step of supplying the purge gas, the step of depositing the silicon nitride film, the step of modifying the silicon nitride film, and the step of supplying the purge gas are successively repeated, by rotating the turntable to cause the substrate to pass through the silicon-containing gas supply area, the first purge gas supply area, the nitriding gas supply area, the treatment gas supply area, and the second purge gas supply area.   
     
     
         13 . The film deposition method according to  claim 12 ,
 wherein a first plasma generator is provided outside the process chamber above the nitriding gas supply area,   wherein a second plasma generator is provided outside the process chamber above the treatment gas supply area, and   wherein the second plasma generator is provided at a position lower than the first plasma generator.